As to DVDs and other recording media, it is sometimes the case that reading errors occur due to scratches on the recording media. Accordingly, playback apparatuses on which such recording media are used generally have a function to detect errors in data when reading the data and correct the detected errors.
Patent Reference 1 discloses a method for efficiently detecting and correcting such data errors on the playback apparatuses.
Specifically speaking, according to the disclosed method, error detection information generated when data was first read is used at the time of reading the data once again, and then only portions in which errors were detected are reread while portions without errors are not subjected to the rereading process.
Herewith, the likelihood that the reread data also includes uncorrectable errors can be reduced, and the data rereading can be conducted in an efficient manner.    <Patent Reference 1> Japanese Laid-Open Patent Application 2000-348446